This application relates to a mixing and folding apparatus, preferably hand driven, and particularly for use in commercial kitchens, for prepartion of various batters, particularly biscuit mixes, food mixes as for souffles, sponge cakes, or mousse.
Foods of this class, items which require the careful mixing together of dry powder-like substance with liquids such as milk, cream, beaten egge white or similar frothy liquids, are not readily prepared in a power driven mixer. Mixing them for too long a period, or at too high a speed, or combinations of such excesses, will result in tough biscuits when baked, or in souffles or mousse which are too thick or flat and have lost the needed "froth" from whiped cream, beaten separated egg whites, or the like. Thus it is often best to utilize a relatively slow-moving beating and/or folding arm, many times a flexible spatula or blade held in the hand or simply the hand itself, which gently lifts and mixes and combines materals placed in a bowl by movng the materials from the bottom of the bowl and depositing them on top of the materials with no strong beating action.
Hand operation gives the chef close control over this action, but to perform this operation in commercial quantities it is necessary to have mixing bowls of a capacity which is greater than can readily be handled with a hand-held spoon, spatula, other tool or the hand itself. As commercial kitchen equipment becoms more and more mechanized, and in the case of fast-food establishments inexperienced part-time help is employed to perform these takss, it has appeared that certain preparation operations, such as the mixing of certain biscuit doughs, the blending of mousse, and the preparation of various sauces, cannot be achieved with good results using standard power-driven food mixers. Such mixers cannot provide the proper mixing action and even if they could, the lowest blending speed available may be too fast for these operations, or it may be difficult to minimize the time of mixing when suing such equipment.
On the other hand, it is necessary to prepare these types of food products in quantities that would require several repetitious uses of a hand mixing bowl and require considerably more time than would be desired, besides some of these more delicate mixes can deteriorate if left to set for any length of time while additional quantities are being prepared.
There is also a class of food preparation devices, known in the trade as cutter-mixers, which employ a tapered symmetrical bowl having a high speed (3600 rev./min.) cutter blade which is mounted directly to a motor shaft entering through the bottom center of the bowl. A typical such device is disclosed in U.S. Pat. No. 4,101,977 issued July 18, 1978. These devices are designed to prepare very quickly large quantities of a wide variety of food products, for example fresh salad mix, meats or vegetables to be finely chopped and mixed, or some doughs.
The blades in these devices are so constructed and driven as to induce a flow of food product in a generally annular path which progresses outward from the blades, upward along the bottom and side of the bowl, then inward and downward as the product loses velocity, returning to the blades. These devices are often equipped with a hand operated mixing baffle which is mounted from a crank at the center of the lid for the bowl, and such baffle extends partially down along the side of such bowl as shown in the above-mentioned U.S. patent. The purpose of this baffle is to remove food product tending to cling to the bowl wall and direct such food product back into the aforementioned annular path. By their very nature, these devices only operate with the bowl axis vertical, although the bowl is often mounted for tilting movement, particularly for unloading of completed product. Further, such mixers are inappropriate for foods of the class which are to be processed by the food mixer/folder of the present application.